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A heat-resistant boehmite-coated polypropylene (PP) membrane has been successfully fabricated and its potential application as a promising separator in the lithium-ion battery was explored. The boehmite powders with average sizes of 0.78, 1.03, and 1.72 μm, respectively, were used to fabricate the coated membrane. It was demonstrated that the coated membrane prepared by boehmite with a 0.78-μm size showed superior heat tolerance and proper air permeability. As compared to the commercialized PP membrane, such coated membrane presented improved electrolyte uptake, better interface stability, and enhanced ionic conductivity. In addition, the lithium iron phosphate (LiFePO4)/Li cell using this composite membrane exhibited better rate capability and cycling retention than that using PP membrane owing to its facile ion transport and excellent interfacial compatibility. The coating layer showed an advantage on solid electrolyte interface film formation and greatly reduced charge transfer resistance. All these fascinating characteristics would boost the application of this composite membrane for high-performance lithium-ion battery.

To improve the performance of lithium-ion batteries, the functional separators were developed by coating water-based polyvinylidene fluoride (PVDF) powder particles solution using polyvinyl alcohol as the binder on both sides of a conventional polypropylene (PP) microporous membrane by means of simple dipping. The electrochemical performance was tested and compared with that of pure PP membrane. It was found that the PVDF powder particles accumulated and scattered on the surface of PP membrane. Many voids existed among the powder particles. The thermal shrinkage percent tested at 130 °C for 1 h was decreased from 59.4% to 12.7%, whereas the electrolyte uptake was increased from 80% to 140%. The separator coated with 10% solid content of PVDF particles exhibited the best electrochemical performance, including the cycling performance and rate capability. The coated PVDF component not only decreased the interface resistance but also increased the ionic conductivity, owing to the high strong affinity of PVDF toward polar solvents and the voids among the PVDF particles to afford the passage for Li-ions.

Despite myriad efforts in the literature designing neural representation system for emotion detection, very few works consider constructing effective model for apperceiving various emotion intensity on social media because of the informal expression and lack of context. In this paper, we proposed a character-aware convolutional recurrent networks with self-attention for emotion detection on user-generated content. The proposed model contains three parts: the character-level convolutional layer is designed to learn word representation based on character n-grams for capturing subword information and independent on pre-trained word embedding. The recurrent neural networks learn the sequential context information used both forward and backward recurrent neural network. And the self-attention module is used to extract different emotion aspects of the sentence into multiple vector representations. The attention module performs on top of recurrent networks which enables attention to be used in special domain or task when there are no extra inputs. We evaluate the proposed model on two public emotion datasets including both emotion intensity detection and emotion classification. We compare our model with the state-of-the-art methods on these datasets and the experimental results demonstrate that the proposed model outperforms several baselines on most emotion types detection and indicates the effectiveness of the designed model. In addition, the training of the proposed model for these tasks relies exclusively on initialized character vector which can be used for morphologically rich languages with long-tailed frequency distributions or domains with dynamic vocabuaries.

In this paper, a stellated carbon filler (S-filler) through passivation of the surfaces of carbon nanotubes and carbon black (CNTs/CB) was fabricated, and the corresponding thermal conductive composites of polypropylene (blended with alumina) (PP/Al 2 O 3 ) incorporated with S-filler were fabricated. When adding 15 wt% S-filler, the composite shows an DC electrical resistivity as high as 8.34 × 10 11 Ω cm and high thermal conductivity about 0.68 W/m·k. The composite using the new carbon filler as hybrid part shows a higher thermal conductivity and electric insulation. The rheological test also shows that the percolation network is not formed by the S-filler. This work offers a novel route for the design of thermally conductive, but electrically insulative composites with polymer as a matrix.